New Study Suggests Levodopa May Slow Progression Of Parkinson Disease

Levodopa is the most powerful drug available to treat the symptoms of Parkinson disease, and almost all patients with the disease will eventually need to take it. But there has long been controversy about when it should be started, in part because of concern that the medicine itself might cause further damage to the brain cells that are impaired in this disease.
http://www.sciencedaily.com/releases/2004/12/041219134001.htm